ABSTRACT
Purpose: Limited data exists on CT chest abnormalities during acute Coronavirus disease 2019 (COVID-19) infection and associated post-illness loss of lung function among lung transplant (LT) patients. Method(s): The institutional database was interrogated for any LT patient diagnosed with COVID-19 during a one-year period (March 2020 to Feb 2021;n=54). 44 patients with acute COVID-19 were alive at 3-month follow up (COVID-survivors: 81.5%). Of the survivors, 34 had a CT chest during the first two weeks of acute illness. A validated CT score was used to quantify the parenchymal abnormalities due to COVID-19. Each lung was divided into 10 separate regions which were scored 0-2 based on the severity and extent of parenchymal opacification (maximum score per lung=20). To avoid confounding from underlying lung disease, only the allograph was assessed in single LT. The average score of both lungs was calculated in bilateral LT. The primary outcome measure was sustained decline of FEV1 or FVC >10% from pre-infection spirometry. Result(s): Abnormal CT score and lung opacities on CT chest were nearly ubiquitous during acute COVID-19 illness (>0;36/37, 97.3%, median score with IDR: 7.25, 4.625-10.125). The lower lobes (LL) were more affected by COVID-19 than the upper and middle lobes (UML) (median CT score in LL: 4, 2.75-6 vs 3.5, 1.25-5 in UML). A >10% decline in FEV1 or FVC was common after COVID-19 pneumonia (38.2%). The overall CT score correlated with amount of lung function loss (r=0.36, p=0.03) although the association was modest and limited to regions reflecting the UML. On ROC curve, CT score was modestly predictive of lung function decline (Fig 1). CT score from UML had the highest area under the curve (78.2%, 61.1-95.4%;p=0.006) with a score of 4.5 being the best cut-off (sensitivity 71%, specificity 85% for post-COVID lung function loss >10%). An UML CT score >4.5 was strongly associated with respiratory failure during acute illness (69% vs 24%;OR: 7.2, 1.5-33.8;p=0.01) and lung function decline >10% (77% vs 19%;OR: 14.2, 2.6-76.7;p=0.001). Conclusion(s): The CT score during acute COVID-19 infection provides prognostic information regarding loss of lung function among LT patients who survive COVID-19. Parenchymal abnormalities in the UML best predict subsequent lung function loss.
ABSTRACT
Purpose: There is limited data on the outcomes beyond the acute illness among lung transplant (LT) patients with Coronavirus disease 2019 (COVID-19). The current study sought to describe the predictors of 6-month survival among a single center cohort of LT. *Methods: We included all the LT patients diagnosed with COVID-19 during a one-year period (March 2020 to Feb 2021;n=54;median age: 60, 20-73 years;M:F 37:17). All patients completed at least 6-month follow up from COVID-19 diagnosis. We reviewed patient characteristics, presenting features, clinical course, and laboratory abnormalities at presentation and during the acute illness. We reviewed the hospital course and post-discharge outcomes including lung function loss among COVID-19 survivors. Median follow-up duration was 304 days. Six-month survival after COVID-19 was analyzed as the primary outcome variable. Result(s): Restrictive lung disease was the most common LT indication (n=41, 75.9%) and most had undergone bilateral LT (n=43, 79.6%). Patients were a median of 48 months (range <1-139 months) from their transplant. Majority of the patients required hospitalization (n=48) and significant proportion of patients developed respiratory failure (n=26). One month survival was 90.7% (n=49) while the survival dropped to 81.5% (n=44) by 6-month follow-up. On univariate analysis, females (35.3% vs 10.8%) and those with pre-existing chronic lung allograft dysfunction (CLAD, 33.3% vs 11.1%) experienced worse 6-month survival. Peak lactate dehydrogenase (LD) levels had the strongest association with 6-month survival on Mann Whitney U comparisons. On receiver operator characteristic curve analysis, the peak LD levels had an area under the curve of 82.9% (69.1-96.7%, p=0.002) with 400 U/L identified as the best cut-off. A peak LD level >400 U/L during the acute illness from COVID-19 was significantly associated with worse 6-month survival (OR, 95% CI: 4.38, 1.31-14.65, p=0.02).On Cox proportion hazard analysis, female gender (adjusted HR: 5.38, 1.13-25.64;p=0.035), pre-infection CLAD (5.63, 1.24-25.57;p=0.025) and peak LD levels >400 U/L (7.49, 1.72-35.53;p=0.007, see Figure for the Kaplan-Meier survival analysis) were independently associated with survival after COVID-19 among LT patients. Conclusion(s): COVID-19 is associated with significant mortality among LT patients with several patients succumbing beyond the period of acute illness. Female gender, established CLAD prior to COVID-19 and an LD>400 U/L at any time during the acute illness are adverse prognostic markers and may form the basis of customized management strategies. (Table Presented).